When novices start to use their first telescope, they look at the sky's major showpieces, such as the Messier nebulae, clusters and galaxies. They're big and bright enough to show up in binoculars, and a beginner's telescope shows detail in many of them. In the background lurk many more faint objects.

Experienced skywatchers buy bigger and better telescopes, seeing ever-richer detail in more and more nebulae, clusters and galaxies. But always, in the background, there are even more objects, too small and faint to make out. Some irreverent amateur astronomers in San Jose call those background objects "Faint Fuzzy Nothings" – FFNs.

FFNs continue in the background as seen by big, professional telescopes, too. Look at a picture of a galaxy in your textbook. In the background you can often notice dim smudges. Each of those is a galaxy, too, but so much farther away that you can't make out as much detail. A 3-meter-wide telescope shows magnificent detail in objects that amateurs can barely glimpse – and in the background lurk uncountable thousands of more FFNs. A 6-meter telescope shows detail in those, and in the background, even more FFNs. A 10-meter telescope reveals detail in those objects ... and in the background, there are ever more FFNs. No telescope has ever been made that didn't find more FFNs in the background.

LBBs

One day when I was visiting my brother, a bird-watcher, I noticed his log of sightings. Almost every entry included "LBB". He told me that LBB stands for "little brown bird". They are so common, so small, and so similar, that they're not worth examining to see which common species each one belongs to. They flock all over, they're usually there, and they're not the big or pretty or rare birds that bird-watchers prize.

LBMs

The university's mycological society hosted a meeting about LBMs. Mycologists study fungi, and I didn't have to attend to figure out that "LBM" stands for "little brown mushroom". LBMs are so common, so small, and so similar, that they're not worth examining to see which common species each one belongs to. They're not the big or pretty or rare mushrooms that fungus-hunters prize.

The same principle applies outside of science. In coin collecting, ignore small copper coins. In stamp collecting, ignore definitives. In antiquarian books, ignore textbooks. And in the serious study of literature, ignore science fiction.

This happens a lot in science. Beginners learn all the kinds of phenomena in the field, and quickly concentrate on certain ones, all but ignoring certain others. Sometimes practicality forces the distinction: some are available, others are too difficult to study. Often, though, it's about what's fashionable to study.

Technology advances at such a furious pace these days that it may be worth looking anew at common background items, using the latest devices. Most people don't pay attention to them. You just might recognize something interesting that no one noticed before.

How does a researcher select what to research? How does an editor select what to publish?

In both processes, the humans involved are often attracted to bright and beautiful objects. For the researcher, "bright" means plenty of light is available, making it practical to take detailed photographs and spectra. For the picture-editor who has to select some items and leave out others, bright and beautiful objects beat dim and ugly ones.

This means that the results reported in textbooks, the press and research journals are not a fair sample.

Red Dwarf Stars

The most abundant type of star seems to be the red dwarf. It's certainly the most abundant type within 25 light years. The very closest star to the Sun, Proxima Centauri, is a red dwarf – but so dim that you need a telescope to see it. Even the brightest red dwarf is too dim to see without binoculars. Since red dwarves are very difficult to recognize, hardly any are known.

For all their abundance, they aren't studied by very many researchers. Compared to other types of stars, they're dimmer, so there is less light to study. They are generally thought to not do much, other than sporadic unpredictable flares, so there is little of interest to attract researchers.

If red dwarves were studied as intently as, say white dwarves or red giants, would more interesting things would be discovered about them?

Thin Nebulae

Bright, thick nebulae get lots of attention. For active nests of stars, for beautiful twists and knots, they look great. There are lots of thinner, dimmer nebulae cataloged, but only a few observers track them down. Mostly, thin, dim nebulae get ignored.

If thin nebulae were studied as much as thick ones, would more interesting things be discovered about them?

Dwarf Elliptical Galaxies

In nearby clusters of galaxies, the most abundant galaxy type is the dwarf elliptical. To see even the brightest requires a significant telescope. Beyond 50,000,000 light years, dwarf ellipticals are very difficult to recognize. Because they are small and faint, not many are known.

For all their abundance, they aren't studied by very many researchers. Compared to other types of galaxies, they're dimmer, so there is less light to study. They are generally thought to not do much, having little nebulosity and no big powerful stars, so there is little of interest to attract researchers.

If dwarf ellipticals were studied as intently as, say, spirals or giant ellipticals, would more interesting things would be discovered about them?

With Galaxies, as With People, Pictures Show the Most Attractive, Not the Most Typical

People who select illustrations for books, slide sets, and other media naturally tend to pick the most attractive examples. This leads to some important misunderstandings. People looking at the examples tend to think they're typical, when actually they are not.

"Spiral" galaxies, which physically are disc galaxies, are prettiest to most humans. Therefore, the prettiest spirals show up in books and slide sets a lot more than others do. Ragged and less-symmetrical spirals, and elliptical and irregular galaxies, hardly ever get selected, even though ellipticals are very abundant.

Most textbooks include a photo of the beautiful galaxy M 51, the "Whirlpool". This is the galaxy with the most obvious spiral appearance; smaller telescopes (perhaps 35 cm) will reveal its arms than any other galaxy's. Many books call M 51 "a typical spiral galaxy". It is actually one of the least typical! Very few disc galaxies have continuous arms that can be traced so far around. Hardly any other bright galaxy has such vivid arms. Enjoy the beautiful view, but don't swallow the claim that it is "typical". It isn't, which is why so many books include it. More typical galaxies don't look as handsome. Editors select the nicest-looking pictures, therefore making the selections anything but "typical".

Barred spirals, too, rarely look like their "typical" case, NGC 1300. That one, again, looks prettier and cleaner than most. That's a good reason to publish its picture, but it's wrong-headed to call it "typical".

Much the same applies to planetary nebulae, pre-stellar nebulae, and surface features on planets. Editors (and often researchers) select the brightest and most attractive ones. Dimmer and less-attractive examples may be more typical, but they're less-often studied and shown.

Contest! Open to all!
Identify the "blandest galaxy", "ugliest galaxy", "blandest nebula", "ugliest nebula", "blandest planetary surface feature", "ugliest planetary surface feature", etc. Winners may be published in later editions of this book, and on this website.

Soon after Nicholas Copernicus published his great book De Revolutionibus in 1543, he died. This prevented the Catholic Inquisition from punishing him for his heresy in moving Earth out of the center, and making it merely one planet among many orbiting the Sun.

Copernicus's Sun-centered system came somewhat closer than anything Ptolemaic to predicting planet positions in the sky. While Copernican predictions were noticeably closer, they were still not exact. We now know the big problem was the shape of the orbits: Copernicus clung to the ancient presumption that orbits must be "perfect" circles. They aren't, but nobody knew that in the 1500s.

Though the Roman Catholic Church emphatically denied Copernican theory - even placing it on its Index of Prohibited Works from 1616 to 1835 - they did permit using it as a handy-dandy computing technique for improved results; it simply must not be taught as "true". 'Go ahead and compute that way to get the best results, but don't believe the system.'

With 20/20 hindsight, some academics have snickered at this, because we know the Earth is not the center of everything. But carry the story a few chapters further:
* Tycho makes the sharpest positional measurements,
* Kepler determines from those that orbits are ellipses, and
* Newton derives Kepler's Laws from his own Law of Universal Gravitation.
* Centuries later, Einstein overthrows Newton, regarding gravity as warps in space-time.

To calculate the path of anything moving many percent of the speed of light requires Einstein's equations; that's how they found out that Newton was wrong. But almost everything that astronomy deals with moves less than 1% of the speed of light. At such slow speeds, the numbers from calculating Einstein's formula are identical with the numbers from calculating Newton's simpler formula. So, even now, practically everybody calculates with Newton's formula, and reserves Einstein's more complicated version for the rare cases where things move really fast. They know Newton is physically wrong, they just use it as a simpler way to compute and get the same result.

What these modern astronomers do is little different from what the Church advocated centuries ago: go ahead and use the handiest formula that gives the best result, but don't believe that it is physically true. To be fair, they should stop snickering at that old Church policy, or start snickering at themselves.